The present invention relates to destructive distillation processes and hydroprocessing units for converting organic wastes and garbage to oils in a system using pressure and heat, especially indirect heat, to mimic but greatly speed natural conversion processes.
Turning garbage economically to oil, like turning lead economically to gold or conducting cold nuclear fusion, is a process long sought but rarely if ever obtained. Baskis of U.S. Pat. Nos. 5,543,061, 5,360,553, and 5,269,947, of Baker U.S. Pat. Nos. 4,636,318, 4,842,692, 4,842,728, and 4,923,604, and of Chen U.S. Pat. Nos. 4,108,730 and 4,175,211, and others are typical of various such efforts. The present inventor has personally worked unsuccessfully for several years, with others, on the Baskis inventions to try actually to perform such a process, before the company doing the development work under license went bankrupt.
Natural processes turn organic material such as plant and animal material to oil or hard coal over, it is believed, hundreds of thousands of years where conditions of pressure, moisture, and temperature are suitable. In modern times, mountains of garbage in landfills are known to give off gases, including methane, as they decompose. Such gases are occasionally gathered and piped for productive uses such as local heating or co-generation of electrical power; otherwise the methane is preferably burned as it escapes through vent pipes from the landfills, to avoid odors and pollution.
Destructive distillation processes are known for the processing and recycling of oils, but none has been successfully applied to converting native organic wastes to oil. Advantages are well known in reducing land fill volumes significantly by diverting or removing and reprocessing organic wastesxe2x80x94just as inorganic iron and other metals, and paper and many plastics are sometimes reprocessed into new metal ingots, paper and paperboard, or plastic materialsxe2x80x94although such processes can be elusive economically.
The object of the present invention is to recycle garbage and organic wastes, including medical waste, into oil in an economical and ecologically sound fashion.
The invention comprises putting bags of waste, or bulk waste, or waste excavated from landfills, through a hopper that feeds to a first auger and then a second auger for compressing and heating the waste. Steam is added to the hopper, and the hopper is under a negative pressure, with exhaust gases going into a safety tank with, for instance, sodium hyperchloride. The exhaust gases also can be treated with ozone or other materials or processes to render them safe before releasing them to the environment. The waste in the hopper may be comminuted by shears or the like, if necessary, before or as it is fed to the first of the heated augers, to improve the processing capabilities and speeds.
Pre-heated, small, solid pieces of inorganic material such as metal balls or hard stones are added to the waste stream in either or both augers to hasten heat transfer into the material and prepare it for treatment. Calcium oxide and/or calcium carbonate may be added to the first auger. The hot material and chemicals help to break and divide the organic material for thorough processing in the first stage and in the second, subsequent autoclave auger stage. Further heat can be added by circulating hot oil through the hollow center cores of the augers.
Steam or hot oil can be added to the first auger for disinfecting raw waste and in an emergency, as, if the auger shaft fails during operation. Steam is also added to the end of the autoclave stage to carry off vaporized volatile components before the balance is passed through a double lock valve and then conveyed to a furnace for combustion. The volatile components are passed through a control valve and a catalyst and then to a condenser for cooling, pressure reduction, and to reduce the oil and water vapor therein to liquid. Remaining gas is fed to the furnace to aid in combustion there. Oil and water are separated after the condenser stage and sent for further processing, as refining and cleaning, or the oil can be used as a heat source in the process.
Heat from the furnace provides much of the energy needed to drive the thermal decomposition of the material in the first and second augers. This heat chiefly goes into the inorganic materials, which then provides a major source of heat for the process. Auxiliary heat supplies of oil, electric, gas, or the like, are also provided to the silo and to the furnace for start-up and when the heat content of the material in the system is insufficient to sustain the reaction processes. Auxiliary heat also is provided by hot oil passing through the hollow shafts of the augers.
Char and inorganic material from the second auger are passed through valves and heated in a furnace, where it is exposed to air for combustion. The material is then dropped onto a vibrating, inclined screen, which separates the material and allows retrieval of the hot metal balls or rocks. Those balls or rocks are then conveyed to a silo and further heated as necessary and then passed back into the first and second stage augers of the system. This system works well with potentially infectious medical waste (PIMW) and all other types of organic materials as to which proper disposition, as well as retrieval of oil contained therein, is critical.